Method and device for directing flow in air-cooled condenser systems

ABSTRACT

The invention relates to methods and devices for directing the flow of air in the suction area formed by the chamber below air-cooled condenser systems that are mounted on support structures and are comprised of air-cooled condensation installations consisting mainly of one vertical plane with air flowing through and of a plane consisting of condenser modules with cooling elements, designed for cooling process and turbine exhaust. In order to prevent the disrupting influences caused by crosswinds, according to the invention, wind deflection panels can be installed in the area of the air intake nozzles and/or near the floor underneath the air-cooled condenser system. The wind deflection panels according to the invention can be installed such that they are static or movable, made of steel construction, or made of other suitable materials, such as canvas, plastic, or wood. If the wind deflection panels are movable, an automatic or manual adjustment to current wind conditions is possible. Advantageously, such wind deflection panels are made of sound-absorbing materials.

The following invention relates to methods and devices for directing the flow of air in the suction area formed by the chamber below air-cooled condenser systems that are mounted on support structures and are comprised of air-cooled condensation installations consisting mainly of one vertical plane with air flowing through and of a plane consisting of condenser modules with cooling elements, preferably in the form of roof panels for cooling process and turbine exhaust. The cooling elements may also be arranged even with the surface.

Air-cooled condenser systems for cooling turbine or process exhaust are generally comprised of identical modules arranged in several parallel rows, adjacent to and behind one another, arranged essentially in a single plane, in a checkerboard pattern. These systems are normally raised on a supporting structure, forming a suction area in the space below. Each module is equipped with a ventilator, which sucks in the cooling air flowing beneath the supporting structure, and forces it essentially vertically through the cooling elements. To enable undisrupted operation, it is necessary for all the ventilators to supply equal quantities of air in order to maintain the basic condensation output. For this reason the modules are placed on a support structure so that it is possible to achieve an even flow of cooling air from all sides.

In the case of a crosswind, air preferably flows toward the condenser system from one direction and thus disrupts the flow field in the suction area beneath the module. As a result, one can observe a subsiding of the quantity of cooling air in parts of the system which in turn will lead to a reduction in condensation output. Experience has shown that the outer windward modules are especially unfavorably affected as the greatest flow rates of the cooling area occur there. As a result, the air-cooled condensers often can no longer ensure the necessary vacuum pressure at the outlet to the turbines, which leads to losses in the efficiency of the power plant. Under unfavorable conditions, the exhaust pressure increases to such a level that to protect the turbines an emergency shut-off must be initiated. Neither a reduction in output nor a complete shut-off of the power plant is acceptable to operators.

To avoid this problem, current technology utilizes wind deflection panels, blocking panels or fine-meshed screens around the periphery or outside the condensation system. These are intended to block wind flow and to ensure an undisrupted airflow field beneath the condensation module. The disadvantage of these solutions is their high cost and the increase in flow resistance for the cooling air, which only can be compensated by an increase in energy consumption by the cooling ventilators. Furthermore, in many cases local features do not allow building modifications to condenser facilities.

The purpose of the invention consists in eliminating or at least largely minimizing the negative effects of crosswind while avoiding the above-discussed disadvantages. This is solved in accordance with the invention by installing baffle plates in the space that forms a suction area beneath the condenser system that is mounted on the supporting structure. Panels designed to direct flow, so-called wind deflection panels, are used as baffle plates. FIG. 1 shows an air-cooled condenser system comprised of four condenser rows, each consisting of six condenser units, in which one preferred design of the wind deflection panels is illustrated. Panels “A” and “B” are therefore arranged so that they are suspended at the height of the ventilator intake nozzles, over the entire length or width of the module rows, wherein the depth of these wind deflection panels that serve to block the air flow is dependent upon the number of modules positioned behind them.

In relation to the clearance below the steel structure, the wind deflection panel in the case “A” between 1/(N−1) and 1/N, wherein “N”=the number of modules that lie one behind the other in the direction of the wind, blocks off the height. With six or more modules, as in the case of the wind deflection panel “B”, the blockade increases to 1/(N−2).

With respect to the outer ventilators, panels “A” and “B” have the effect of collecting the flow of air below the cooling air intake of the ventilators, thus improving the supply of air. The advantage is thus that even the kinetic energy contained in the wind is utilized. Surprisingly, tests have shown that the optimized arrangement of the wind deflection panels generates no additional drop in pressure for the ventilators; but, in contrast, a tendency towards improved supply to the modules is ensured. Because the wind deflection panels only block approximately that portion of the cross-section of the flow of cooling air that corresponds to the portion of the flow of cooling air that corresponds to the modules, the modules that lie behind the blocking panels are not affected, or are only slightly affected.

In another favored design, additional wind deflection panels “C” are installed at a height slightly above the base. These panels serve to ensure an improved bombardment with air of the modules that lie directly behind the upper dividing panels “A” and “B”. The height of these wind deflection panels “C” installed near the base preferably amounts to 1/N, a maximum of ¼ of the clearance height of the supporting structure. The preferred ground clearance is approximately 1 m, but if the system is large enough this can also be increased to approximately 2 m to allow easier access to the system. These base panels “C” give an advantageous upward component to the cooling air flowing beneath the modules. The use of such wind deflection panels near the base is dependent upon local conditions, especially main wind direction.

The wind deflection panels “A”, “B”, and “C” can be made of steel; however, other materials such as canvas, plastics, or wood are also suitable for use. The panels can be designed to be static or movable, e.g. in the form of roll-up panels or venetian blinds. The movable design for the wind deflection panels enables adjustment to current wind conditions, especially wind direction, and wind speed.

Adjustment of such movable panels can be automatic or manual. Advantageously, the wind deflection panels according to the invention can be made of sound-absorbing materials, allowing the noise emissions from the air-cooled condenser system to be further reduced.

Advantageously, the wind deflection panels according to the invention can be integrated not only into newly constructed air-cooled condenser facilities; but, a modernization of already existing condenser facilities is also possible.

List of References for Illustration

-   A suspended wind deflection panel -   B suspended wind deflection panel -   C wind deflection panel near base -   W wind direction 

1. Method for directing the flow of air in the suction area formed by the chamber below air-cooled condenser systems that are mounted on support structures and are comprised of air-cooled condensation installations consisting mainly of one vertical plane with air flowing through and of a plane consisting of condenser modules with cooling elements, preferably in the form of roof panels for cooling process and turbine exhaust, characterized to influence flow so that at least one baffle plate is installed inside the suction space.
 2. Method according to claim 1, characterized by the baffle plate being formed by at least one wind deflection panel.
 3. Method according to claim 2, characterized by the fact that the wind deflection panels installed are arranged to influence flow behavior suspended inside the suction area at the height of the ventilator intake nozzles over a part or the entire length and/or width of the rows formed by the individual condenser modules.
 4. Method according to claim 1, characterized by wind deflection panels designed to influence flow behavior of the air in the suction area with a vertical extension relative tot eh clearance of the suction area below the condensation modules of 1/(N−2) to 1/N, wherein N=the modules that lie one behind the other in the direction of flow.
 5. Method according to claim 1, characterized by wind deflection panels designed to influence the flow behavior of air in the suction area and installed near the base up to 2 m above the base in the suction area.
 6. Method according to claim 4, characterized by wind deflection panels positioned near the base up to 2 m above the base in the suction area with a vertical extension of a maximum of ¼ of the clearance height of the suction area below the condensation modules.
 7. Method according to claim 5, characterized by wind deflection panels designed to influence the flow behavior of air and arranged over a part or the entire length and/or width of the suction area below the condensation modules.
 8. Method according to claim 1, characterized by wind deflection panels designed to influence flow behavior by being made of steel.
 9. Method according to claim 1, characterized by wind deflection panels designed to influence flow behavior and made of suitable materials such as canvas, plastic or wood.
 10. Method according to claim 1, characterized by wind deflection panels designed to influence flow behavior and installed such that they are static.
 11. Method according to claim 1, characterized by wind deflection panels designed to influence flow behavior and installed such that they are movable.
 12. Method according to claim 11, characterized by movable wind deflection panes designed to influence flow behavior and installed as roll-up panels or Venetian blinds.
 13. Method according claim 11, characterized by movable wind deflection panels designed to influence flow behavior that can be controlled automatically or manually.
 14. Method according claim 1, characterized by wind deflection panels designed to influence flow behavior and designed of sound-absorbing materials.
 15. Device for influencing the flow of air in the suction area that is formed by the chamber below air-cooled condenser systems that are mounted on a support structure and are comprised of condensation installations that are arranged essentially on a vertical plane with air flowing essentially vertically, with cooling elements for cooling process and turbine exhaust, characterized by the device being formed by a baffle plate.
 16. Device according to claim 15, characterized by the baffle plate that is formed by at least one wind deflection panel.
 17. Wind deflection panels according to claim 15, characterized by the fact that these are arranged, suspended at the height of the ventilator intake nozzles over a portion or the entire length and/or width of the rows that are formed by the individual condensation modules.
 18. Wind deflection panels according to claim 16, characterized by having a vertical extension relative to the clearance of the suction area below the condensation modules of 1/(N−2) to 1/N, wherein N=the number of modules that lie one behind the other in the direction of flow.
 19. Wind deflection panels according to claim 16, characterized by installing them in the suction area near the base, up to 2 m above the base.
 20. Wind deflection panels according to claim 19, characterized by having a vertical extension of preferably 1/N, a maximum of ¼ of the clearance height of the suction area below the condensation modules.
 21. Wind deflection panels according to claim 19, characterized by being arranged in the suction area over a part or the entire length and/or width of the rows formed by the individual condenser modules.
 22. Wind deflection panels according to claim 15, characterized by being made of steel.
 23. Wind deflection panels according to claim 15, characterized by being made of suitable materials, such as canvas, plastic, or wood.
 24. Wind deflection panes according to claim 15, characterized by being installed so that they are static.
 25. Wind deflection panels according to claim 15, characterized by being installed so that they are movable.
 26. Wind deflection panels according to claim 25, characterized by being movable wind deflection panels and installed as roll-up panels or Venetian blinds.
 27. Wind deflection panels according to claim 25, characterized by the fact that these movable wind deflection panels can be controlled automatically or manually.
 28. Wind deflection panels according to claim 15, characterized by wind deflection panels made of sound-absorbing material. 